In electronic equipment, such as television receivers or other consumer products, switch mode power supplies may be economically used. These switch mode power supplies provide control or regulation of, for example, a relatively high level operating voltage, such as the B+ scan supply voltage for the line output stage of a television receiver. The regulation is performed on the secondary side of the switch mode power supply transformer by comparing an operating voltage level with a nominal value. The result of the comparison is transferred to the primary side of the switch mode power supply to control a pulse width modulator or other control circuit which supplies trigger pulses to the electronic switch of the switch mode power supply.
Because only the B+ operating voltage is directly sensed and controlled, other operating voltages generated by the switch mode power supply, such as lower potential operating voltages, may require further regulation. These voltages may require further regulation because they may be loaded differently and because their associated loads may require tighter voltage regulation.
To achieve further regulation, it is known to use linearly operated regulators which are expensive and lossy. A feature of the invention is the stabilization or regulation of the lower potential operating voltages in a manner that provides for reduced power dissipation in the regulator.